Abstract: Exhaust gas systems include an oxidation catalyst (OC) capable of receiving exhaust gas and oxidizing one or more of combustible hydrocarbons (HC) and one or more nitrogen oxide (NOx) species, a selective catalytic reduction device (SCR) disposed downstream from and in fluid communication with the OC via a conduit, and an electrically heated catalyst (EHC) disposed at least partially within the conduit downstream from the OC and upstream from the SCR. The EHC comprises a heating element having an outer surface including one or more second oxidation catalyst materials capable of oxidizing CO, HC, and one or more NOx species. The OC includes one or more storage materials individually or collectively capable of storing NOx and/or HC species. Exhaust gas can be supplied by an internal combustion engine which can optionally power a vehicle.

Abstract: Exhaust gas systems include an oxidation catalyst (OC) capable of receiving exhaust gas and oxidizing one or more of combustable hydrocarbons (HC) and one or more nitrogen oxide (NOx) species, a selective catalytic reduction device (SCR) disposed downstream from and in fluid communication with the OC via a conduit, and an electrically heated catalyst (EHC) disposed at least partially within the conduit downstream from the OC and upstream from the SCR. The EHC comprises a heating element having an outer surface including one or more second oxidation catalyst materials capable of oxidizing CO, HC, and one or more NOx species. The OC includes one or more storage materials individually or collectively capable of storing NOx and/or HC species. Exhaust gas can be supplied by an internal combustion engine which can optionally power a vehicle.

Abstract: Selective catalytic reduction filter (SCRF) devices and systems incorporating the same are provided. Systems can include an exhaust gas source, an exhaust gas conduit capable of receiving an exhaust gas stream from the exhaust gas source, and an SCRF device in fluid communication therewith. The SCRF device can include a filter, a selective catalytic reduction (SCR) catalyst disposed on at least portion of the filter, and a NOx storage coating on at least a portion of the filter. The NOx storage coating can include one or more of palladium, barium, or cerium. The NOx storage coating can be biased towards the upstream side of the filter. The NOx storage coating can overlap a portion of the SCR catalyst. The system can further include a water-absorbing alkali oxide. The water-absorbing alkali oxide can be disposed within the SCRF device, the exhaust gas conduit, or in an upstream oxidation catalyst device.

Abstract: Electric heaters comprising corrosion resistant metals (CRM), and exhaust gas treatment systems incorporating the same, are provided. Exhaust gas treatment systems include selective catalytic reduction devices (SCR) disposed downstream from reductant injectors. Electric heaters can be disposed downstream from reductant injectors, and optionally contiguous with or incorporated with a catalytic composition of the SCR. CRMs resist corrosion to reductant, which includes t ammonia and/or nitrogen-rich substances capable of decomposing into ammonia, such as urea. CRMs include aluminum, chromium, iron, and one or more stabilizers. CRMs can include about 5.0% to about 7.25% aluminum, about 15% to about 25% chromium, up to about 0.30% stabilizers, and a balance comprising iron. Stabilizers can include hafnium, yttrium, and zirconium. Stabilizers can include about 0.001% to about 0.11% yttrium and about 0.001% to about 0.11% Hf.

Abstract: Selective catalytic reduction filter (SCRF) devices and systems incorporating the same are provided. Systems can include an exhaust gas source, an exhaust gas conduit capable of receiving an exhaust gas stream from the exhaust gas source, and an SCRF device in fluid communication therewith. The SCRF device can include a filter, a selective catalytic reduction (SCR) catalyst disposed on at least portion of the filter, and a NOx storage coating on at least a portion of the filter. The NOx storage coating can include one or more of palladium, barium, or cerium. The NOx storage coating can be biased towards the upstream side of the filter. The NOx storage coating can overlap a portion of the SCR catalyst. The system can further include a water-absorbing alkali oxide. The water-absorbing alkali oxide can be disposed within the SCRF device, the exhaust gas conduit, or in an upstream oxidation catalyst device.

Abstract: A reductant dosing control system, for use in a Selective Catalytic Reduction (SCR) system of a motor vehicle includes an input receiving a NOx feedback signal from an NOx sensor provided to the SCR system. A base dosing module calculates a required quantity of reductant to inject in front of a SCR catalyst of the SCR system based on the NOx feedback signal. The SCR catalyst has ammonia storage properties. An output signals a reductant metering mechanism to periodically or continuously inject excess reductant based on the required quantity of reductant.